Encapsulated antimicrobial material

Abstract

The present invention provides an antimicrobial material in an encapsulated form, comprising (i) a core comprising an antimicrobial material and (ii) a shell of encapsulating material, wherein the shell of encapsulating material is impermeable to the antimicrobial material. The invention further provides a process for introducing an antimicrobial material into a foodstuff comprising (i) providing the antimicrobial material in an encapsulated form comprising a core of antimicrobial material and shell of encapsulating material, and (ii) introducing encapsulated antimicrobial material into or onto the foodstuff.

1. An antimicrobial material in an encapsulated form, comprising (i) a core comprising an antimicrobial material is at least selected from nisin and natamycin, wherein the core includes a lipid and (ii) a shell of encapsulating material, wherein the shell comprises a triglyceride, wherein the shell of encapsulating material is impermeable to the antimicrobial material and comprises a hydrophobic shell material having a melting point above about 45° C., and wherein the shell prevents, reduces or inhibits heat degradation of the antimicrobial material when heated to a temperature of at least 60° C. 
     
     
       2. An antimicrobial material according to  claim 1  wherein the antimicrobial material is present in an amount to provide a microbicidal or microbiostatic effect. 
     
     
       3. An antimicrobial material according to  claim 2  wherein the microbicidal or microbiostatic effect is a bactericidal or bacteriostatic effect. 
     
     
       4. An antimicrobial material according to  claim 3  wherein the bactericidal or bacteriostatic effect is in respect of Gram-positive bacteria. 
     
     
       5. An antimicrobial material according to  claim 3  wherein the bactericidal or bacteriostatic effect is in respect of an organism selected from species of  Bacillus , species of  Clostridium, Listeria monocytogenes , lactic acid bacteria,  Leuconostoc, Carnobacterium, Enterococcus; Brochothrx thermosphacta  and  Lactobacillus  species. 
     
     
       6. An antimicrobial material according to  claim 3  wherein the bactericidal or bacteriostatic effect is in respect of  Listeria monocytogenes.    
     
     
       7. An antimicrobial material according to  claim 1  wherein the shell provides sustained release of the antimicrobial material from the encapsulated antimicrobial material. 
     
     
       8. An antimicrobial material according to  claim 1  wherein the shell releases the antimicrobial material from the encapsulated antimicrobial material under predetermined conditions. 
     
     
       9. An antimicrobial material according to  claim 1  wherein the shell releases the antimicrobial material from the encapsulated antimicrobial material on contact with a foodstuff. 
     
     
       10. An antimicrobial material according to  claim 9  wherein the foodstuff is a marinade. 
     
     
       11. An antimicrobial material according to  claim 1  wherein the shell of the encapsulated antimicrobial material is capable of withstanding injection. 
     
     
       12. An antimicrobial material according to  claim 1  wherein the shell of the encapsulated antimicrobial material is capable of withstanding a pressure of greater than 1.5 bar. 
     
     
       13. An antimicrobial material according to  claim 1  wherein the encapsulated antimicrobial material is a particulate form. 
     
     
       14. An antimicrobial material according to  claim 1  wherein the encapsulated antimicrobial material has an average particle size of less than 150 μm. 
     
     
       15. An antimicrobial material according to  claim 1  wherein the shell provides sustained release of the antimicrobial material from the encapsulated antimicrobial material. 
     
     
       16. An antimicrobial material according to  claim 1  wherein the triglyceride is a vegetable triglyceride. 
     
     
       17. An antimicrobial material according to  claim 1  wherein the encapsulated antimicrobial material is prepared by a process selected from spray cooling, and fluidised bed coating. 
     
     
       18. An antimicrobial material according to  claim 1  wherein the encapsulated antimicrobial material further comprises a chelator. 
     
     
       19. An antimicrobial material according to  claim 18  wherein the chelator is selected from EDTA, citric acid, monophosphates, diphosphates, triphosphates and polyphosphates. 
     
     
       20. An antimicrobial material according to  claim 18  or  19  wherein the chelator enhances the antimicrobial activity and/or antimicrobial spectrum of the antimicrobial material. 
     
     
       21. An antimicrobial material according to  claim 18  wherein the chelator enhances the antimicrobial activity and/or antimicrobial spectrum of the antimicrobial material in respect of Gram-negative bacteria. 
     
     
       22. A composition comprising
 (i) an encapsulated antimicrobial material as defined in  claim 1 ; 
 (ii) a carrier. 
 
     
     
       23. A composition according to  claim 22  wherein the carrier is or comprises brine. 
     
     
       24. A composition according to  claim 22  wherein the carrier and the encapsulated antimicrobial material have substantially the same density. 
     
     
       25. A composition according to  claim 22  wherein the encapsulated antimicrobial material is modified to have substantially the same density as the carrier. 
     
     
       26. A composition according to  claim 25  wherein the encapsulated antimicrobial material is modified by contacting the encapsulated antimicrobial material with oil. 
     
     
       27. A composition according to  claim 26  wherein the oil is brominated oil. 
     
     
       28. A composition according to  claim 26  wherein the carrier is modified to have substantially the same density as the encapsulated antimicrobial material. 
     
     
       29. A composition according to  claim 28  wherein the carrier comprises xanthum gum. 
     
     
       30. A composition according to  claim 22  wherein the carrier comprises an emulsifier. 
     
     
       31. A protected foodstuff comprising
 (i) a foodstuff, and 
 (ii) an antimicrobial material according to  claim 1  or a composition according to  claim 22 . 
 
     
     
       32. A protected foodstuff according to  claim 31  wherein the foodstuff is selected from raw meat, cooked meat, raw poultry products, cooked poultry products, raw seafood products, and cooked seafood products. 
     
     
       33. A protected foodstuff according to  claim 32  wherein the foodstuff is raw meat. 
     
     
       34. A protected foodstuff according to  claim 32  wherein the foodstuff is a raw or cooked poultry product. 
     
     
       35. A protected foodstuff according to  claim 31  or  32  wherein the foodstuff comprises whole meat muscle. 
     
     
       36. An antimicrobial material according to  claim 1  wherein the shell consists of a triglyceride. 
     
     
       37. An antimicrobial material according to  claim 1  wherein the core is solid. 
     
     
       38. A process for introducing an antimicrobial material as defined in  claim 1  into a foodstuff comprising
 (i) providing the antimicrobial material in an encapsulated form comprising a core of antimicrobial material and shell of encapsulating material; and 
 (ii) introducing the encapsulated antimicrobial material into or onto the foodstuff. 
 
     
     
       39. A process according to  claim 38  wherein the encapsulated antimicrobial material is introduced into or onto the foodstuff by (a) injecting the encapsulated antimicrobial material into the foodstuff or (b) tumbling the encapsulated antimicrobial material with the foodstuff. 
     
     
       40. A process according to  claim 38  or  39  wherein the encapsulated antimicrobial material is introduced into the foodstuff by injecting the encapsulated antimicrobial material into the foodstuff. 
     
     
       41. A process according to  claim 38  or  39  wherein the encapsulated antimicrobial material is introduced into or onto the foodstuff by tumbling the encapsulated antimicrobial material with the foodstuff. 
     
     
       42. A process according to  claim 38  wherein
 (i) the antimicrobial material is at least nisin, 
 (ii) the antimicrobial material is present in an amount to provide a microbicidal or microbiostatic effect in respect of  Listeria monocytogenes,    
 (iii) the shell is selected to prevent, reduce or inhibit degeneration or inactivation of the antimicrobial material by one or more factors selected from heat degradation, pH induced degradation, protease degradation and glutathione adduct formation; and 
 (iv) the foodstuff is selected from raw meat products, cooked meat products, raw seafood products, cooked seafood products, raw poultry products and cooked poultry products. 
 
     
     
       43. A foodstuff prepared by a process as defined in  claim 38 . 
     
     
       44. A foodstuff obtainable by a process as defined in  claim 38 . 
     
     
       45. An antimicrobial material in an encapsulated form, comprising (i) a core comprising an antimicrobial material selected from nisin and natamycin, wherein the core includes a lipid and (ii) a shell of encapsulating material, wherein the shell prevents, reduces or inhibits heat degradation of the antimicrobial material when heated to a temperature of at least 60° C.